• Toxicological Research
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• v.22 no.1
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• pp.39-45
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• 2006

As the antioxidant and free radical scavenger, glutathione (GSH) participates in the preservation of cellular redox status and defense against reactive oxygen species and xenobiotics. Glutamate-cysteine ligase (GCL; also known as ${\gamma}$-glutamylcysteine synthetase, EC 6.3.2.2) is the rate limiting enzyme in GSH synthesis. In the present study, the accurate method for determination of GCL activity in crude liver extracts was developed by measuring both ${\gamma}$-glutamylcysteine and GSH from cysteine in the presence of glutamate, glycine and an ATP-generating system. We added glycine to promote the conversion of ${\gamma}$-glutamylcysteine to GSH, and to minimize the possibility of ${\gamma}$-glutamylcysteine metabolism to cysteine and oxoproline by ${\gamma}$-glutamylcyclotransferase. We established optimal conditions and substrate concentrations for the enzyme assay, and verified that inhibition of GCL by GSH did not interfere with this assay. Therefore, this assay of hepatic GCL under optimal conditions could provide a more accurate measurement of this enzyme activity in the crude liver extracts.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.598-601
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• 2001

Citrobacter sp. Y19 was studied for $H_2$ production from glucose in batch culture. Important conditions studied include phosphate concentration, temperature, glucose concentration, and gas-phase replacement. Optimal $H_2$ production was observed at 140 - 180 mM of phosphate and $36^{\circ}C$. When glucose concentration increased from 0.1 to 5% (w/v), $H_2$ production increased up to 2% and remained constant thereafter. Intermittent purging of the reaction bottle with Ar gas stimulated the $H_2$ production by alleviating the inhibition by $H_2$. The maximum productivity was observed to be 113.2 ml $H_2$/h-1.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.69-73
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• 2015

The world is presently facing key challenges due to the population explosion, shortages in renewable sources of energy, and environmental problems. One important aspect of ecological intensification is the use and improvement of marginal lands and spaces often ignored, until now. Goats are known to be well adapted to scrubs, forage trees, and rangelands. Goats could contribute marginally, but significantly, to the growing demand for meat without using arable lands. Since 2000, there were 752 million goats globally, and goat livestock increased by 26.8% in 2010, accounting for 954 million heads. Goats are widespread due to their high adaptability to different environmental conditions and nutritional regimes, high productivity, and low maintenance cost. A significant growth in goat number was noticed in the period 2000~2010 in the Netherlands (+113.83%), in spite of the 9.75% decrease in EU-27. A cheese making goat farm in the Netherlands showed how it can survive in the one fifth size of the average. It may be a good model for the Korean goat industry since it uses seasonal breeding and results in reduced "goaty" flavor in the cheese.

• Mycobiology
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• v.38 no.3
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• pp.189-194
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• 2010

This study investigated the cultural characteristics of Shimizuomyces paradoxus in different nutritional and environmental conditions. The highest mycelial growth was observed in Schizophyllum (mushroom) genetics complete medium plus yeast extract agar medium, and the optimal temperature and pH were $25^{\circ}C$ and pH 8.0, respectively. The optimal carbon and nitrogen sources were 1% dextrose and 1% peptone in agar. However, in liquid culture the highest dry mycelium weight was found for the potato dextrose agar and potato sucrose agar broths. The optimum inoculum size was five mycelial discs (5 mm) per 100 mL of broth, and the optimum liquid culture period was 25 days. This is the first ever report of S. paradoxus cultural characteristics.

• Mycobiology
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• v.31 no.1
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• pp.36-41
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• 2003

Influence of physiological and environmental factors on an antagonistic strain of Trichoderma viride RSR7 were studied optimize its biocontrol potential. The growth and sporulation of T. viride was greatly influenced by various carbon and nitrogen sources, and the environmental factors such as pH and temperature. The best growth and sporulation of T. viride was observed when sucrose, peptone and trehalose were supplemented in the medium as sole carbon sources. Rhamnose, pyruvic acid and sorbitol also supported a good growth. However, with these carbon sources the sporulation was poor. Growth and sporulation was also affected by various nitrogen sources. Growth and sporulation both were favoured by ammonium forms of nitrogen compared to nitrite or nitrate forms. Urea did not support either growth or sporulation. Among amino acids, glutamic acid, asparagine, leucine, aspartic acid, glutamic acid and alanine supported good growth as well as sporulation. T. viride was able to utilize large number of amino acids as sole nitrogen source. Proline was good for growth, but not for sporulation. Maximum growth and sporulation of T. viride was between pH 4.5 to 5.5. Temperatures between $20^{\circ}C\;and\;37^{\circ}C$ were good for both growth and sporulation of T. viride. At lower temperatures(i.e. below $20^{\circ}C$) growth and sporulation were inhibited. Based on the present study it may be concluded that T. viride RSR7 is capable of growing and sporulating with varied nutritional and environmental conditions and, therefore, this strain of T. viride may be useful as a biocontrol agent under diverse physiological and environmental conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1353-1362
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• 2005

The stressful physiological and environmental conditions around weaning often promote the proliferation of pathogens in the digestive tract of piglets resulting in diarrhoea and reduced daily weight gain. Typical dietary practices to maintain growth performance and health have led to an increased use of antimicrobial growth promoters. Due to the advanced ban of antibiotics in pig production, new concepts have been developed to secure animal health and growth performance, feed efficiency, and product quality as well. Several naturally occurring compounds seem to beneficially affect the composition and activity of the microflora in the gastrointestinal tract (GIT) of pigs. These are, among others, organic acids, probiotics, prebiotics, and enzymes. Organic acids are already widely used, especially in pigs, due to their positive effects on GIT health and growth performance. Probiotics have been shown to be effective against diarrhoea though effects may be dependent on diet composition and environmental conditions. Prebiotics may influence composition and activity of the intestinal microflora. Additionally, pre- and probiotics may exert positive influences on immune response, whereas enzymes may enhance feed digestibility by breaking down anti-nutritional factors. In the following, the focus will be directed to the role of organic acids, probiotics, prebiotics, and feeding enzymes as potential modulators of GIT health.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.315-322
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• 2013

BACKGROUND: This study was performed for the identification and quantification of glucosinolate (GSL) contents in seven varieties of rapeseed (Brassica napus L.) sprouts cultivated under dark and light conditions. METHODS AND RESULTS: Crude glucosinolates (GSLs) were desulfated by treating with aryl sulfatase and purified using diethylaminoethyl sepharose (DEAE) anion exchange column. Individual GSLs were quantified using high-performance liquid chromatography (HPLC) with electrospray ionization-tandem mass spectrometry (ESI-MS/MS). Eleven GSLs including six aliphatic (progoitrin, sinigrin, glucoalyssin, gluconapoleiferin, gluconapin, and glucobrassicanapin), four indolyl (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin) and one aromatic (gluconasturtiin) were identified based on the fragmentation patterns of MS spectrum. Aliphatic GSLs were noted as the predominant group with average 85.2% of the total contents. The most abundant GSLs were progoitrin which was ranged at $8.14-118.68{\mu}mol/g$ dry weight (DW). The highest total GSL amounts were documented in 'Hanra' ($146.02{\mu}mol/g$ DW) under light condition and 'Mokpo No. 68' ($86.67{\mu}mol/g$ DW) in dark condition, whereas the lowest was in 'Tamra' (30.13 and $14.50{\mu}mol/g$ DW) in both conditions. The sum of aliphatic GSLs attributed > 80% in all varieties, except 'Tamra' (67.7% and 64.9% in dark and light conditions, respectively) in the total GSL accumulation. Indolyl GSLs were ranged $2.41-15.73{\mu}mol/g$ DW, accounted 2.78-33.6% of the total GSLs in rapeseed varieties. CONCLUSION(S): These results provide valuable information regarding potential beneficial GSL contents individually. This study attempts to contribute to knowledge of the nutritional properties of the different varieties of rapeseed plants. These results may be useful for the evaluation of dietary information.

• Journal of the Korean Society of Food Culture
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• v.38 no.2
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• pp.119-127
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• 2023

The labor environment in Korea has changed and problems related to employment types are treated as important issues. Especially, the ratio of irregular workers has not only increased relatively, but the labor conditions in Korea also have worsened in the current years. Studies have reported an association between temporary workers and the prevalence of diseases. However, there is insufficient research on chronic disease and employment types. Methods: The current study examines the prevalence rate of diseases and health behavior by categorizing employment types among Korean adults. Data were obtained from the 2016-2018 Korea National Health and Nutrition Examination Survey. Totally, the data of 2,366 workers (1,239 regular and 1,127 irregular) were analyzed in the study. The types of employment were classified by a questionnaire querying about working conditions. The results showed that irregular workers earned less than regular workers and had a significantly higher prevalence of diabetes mellitus and hypertension. We propose that if discrimination related to working conditions were relieved, irregular workers would be able to invest more time to exercise and doing check-ups regularly. In addition, individual nutrition consultations considering the knowledge and personal environmental factors of each individual are necessary for the improved health of all workers.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.1
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• pp.39-48
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• 2015

This study aimed to compare and evaluate nutritive conditions of the female elderly (2,893 people) based on a national health nutrition survey and health-related factors influencing nutritional intake. The results are as follows.- Average age of all subjects was $72.12{\pm}5.2$ old. BMI ($24.48{\pm}3.3kg/m^2$) and waist size ($83.9{\pm}9.5cm$) of urban elderly was larger ($23.74{\pm}3.3kg/m^2$, $82.28{\pm}9.9cm$) than that of rural elderly. MAR[4] and MAR[10] were also higher in urban elderly than rural elderly. The results of multiple regression analysis showed that factors influencing poor nutrition of elderly subjects were increasing age, smoking, and self-rated health. Old-old and current smokers were associated with a higher likelihood of poor nutrition (OR 1.82, 95%CI 1.43~2.30) and (OR 3.40, 95%CI 2.17~5.33) elderly female subjects in urban areas. Smoking (OR 2.29, 95%CI 1.33~3.95), poor self-rated health (OR 1.55, 95%CI 1.11~2.16), over nine hours of sleep per nighting (OR 1.72, 95%CI 1.17~2.53) and stress (OR 1.46, 95%CI 1.10~1.92) of elderly female subjects in rural areas were associated with higher likelihood of a poor nutrition. In conclusion, rural elderly are more influenced by poor health practice behaviors (self-rated health, sleeping stress) and psychological factors. Nutrition status of the rural elderly is worse than that of the urban elderly. To reduce nutritional risk of Korean elderly, especially rural elderly, active nutrition arbitration should include psychological environmental factors.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.351-368
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• 2004

Following the previous experiments, a starvation experiment was conducted to determine the influence of feeding and starvation on the histological and biochemical changes, the morphormetric changes in the sectioned body and the morphometric changes in Rhynchocypris oxycephalus (Sauvage and Dabry). The influence of starvation on nutritional conditions of the histological changes of hepatocyte and intestinal epithelium as hepatosmatic index (HSI), protein, RNA and DNA concentrations of liver in R. oxycephalus was tested. Although the starved group showed higher concentrations of protein, DNA and RNA than the fed group, food deprivation resulted in a decrease in the HSI, hepatocyte nucleus size and nuclear height of the intestinal epithelium. The RNA - DNA ratio appears to be a useful index of nutritional status in R. oxycephalus and may be useful for determining if R. oxycephalus is in a period of rapid or slow growth at the time of sampling. Additionally, the data have been interpreted in detail and some biologically important relationships discussed. The effects of starvation on the morphometrical changes in sectioned body traits, condition factor, viscera index and dressing percentage were determined for evaluating nutritional conditions of R. oxycephalus. Starvation for nine weeks resulted in a decrease in most sectioned traits as well as in condition factor and viscera index (P<0.05). These findings suggest that nutritional parameters used in this study appear to be a useful index for nutritional status in this species. The data has been interpreted in detail and some important body sectioned values of interest to commercial growers discussed. A 75-day study was conducted to determine the effect of starvation on classical and truss parameters in R. oxycephalus. Truss dimensions of almost the entire head and trunk region as well as the abdomen were increased significantly through feeding or starvation (P<0.05). Truss dimensions of the caudal region generally decreased through feeding or starvation, particularly those dimensions at the hind part of the trunk. There were some significant decreases in classical dimensions of the head region during feeding, in relation to body depth characteristics in the trunk and caudal region during starvation, whereas there was only one decreasing classical dimension in the caudal region during feeding. The results of this study indicate that application of the truss network as a character set enforces classical coverage across the body form, discrimination among experimental groups thus being enhanced. Considering that the dimension of the lower part of the head and some truss and classical dimensions were least affected by feeding and starvation, these dimensions may then be useful as a taxonomical indicator to discriminate the species of Rhynchocypris sp. The value of trunk region dimensions with a large component of body depth in R. oxycephalus is most likely to be compromised by variability related to differences in feeding regimes of fish in different habitats.